let arra = [1, 2, 3]
arra.forEach(item => {
  console.log(item);
})
function Person() {
  this.name = '666'
}
function Hh() {
  this.gage = '10000'
}
let p = new Person()
Hh.prototype = p
let ppage = new Hh()
for(let k in ppage) {
  if(k === 'a') continue
  console.log(k)
}